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, Wed, 10 Feb 2016 16:14:26
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The staggering/stuttering happens maybe 80-90% of the time I'm driving even for a few minutes, even in very cold weather when I doubt the fans would come on, with the consequent electrical load that one of the gangs mentioned here. It only happens when I'm in gear and either just idling along, with the revs drooping to 1,500 or less, or decelerating, in gear. Again, if I depress the clutch, leaving the tranny in gear, the staggering ceases immediately and the engine idles smoothly at about 900 rpm. Also, in response to another query regarding the last three digits of part number of the ignition computer requested by another respondent above, I may have given the wrong number: the correct last three digits may be 812.
I've been further corresponding with my Indy, who clearly knows C900s, although these days they are now very thin on the ground here in the Frozen Prairie.
Regarding ECU failure/defect, while still trying to sort this out myself a year ago, I tried running the AMM self-test in Bentley, which should have shown the AMM heater wires incandescing something like 30 secs after engine shutdown. They never would, in about three tries, so maybe the ECU has been problematic all along.
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"Hi Jeyi
OK...
If you look back at my earlier emails to you, I mentioned about the ECU. The only thing that was not sitting right with me was the lack of idle air control movement at idle. Now this is important because it not only could effect idle, but inherently effect the overall performance adjustments from the ECU. IE..injector and ignition timing. Your 93 has computer controlled ignition timing and injection. I was getting a 5V reffrence at the IAC but hardly any voltage for idle adjustment. I swapped out your IAC with one I had and no change. Thats why I had some doubt about the ECU. Now a AMM could also effect fuel delivery tremendously..however, I tried your used one and one of my used ones with no change to the idle or cold start. Now this staggering...i must be honest...I never really felt driving it. When I first pulled the car in, it would hardly accelerate when cold...after I replace the ECT and O2 sensor, that changed completely. But the staggering issue im a little confussed. If I were to do a next step, I would like to see what another ECU would do...only for the fact of the missing/almost not movement voltage for the IAC...that should not be like that. (or possible wiring issue some where.) Also, there are a bunch of grounds tied together and bolted to the cylinder head. I removed them and cleaned...no change. That was also a common issue.
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Yo, Indy...
E-bay is full of used Bosch Jetronic ECUs for $40-$150. What is your suggestion of where I/we go from here?
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Jeyi, I would grab one cheap and get it. I can plug it in pretty easily to see what effect it has. I know its kinda a shot in the dark, but again, the IAC circuit is not right, and that gets controlled directly from the ECU.
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Yo, Indy... Just ordered one for $65, used. Should be here next week. Will call you when it comes.
posted by 73.246.119...
, Wed, 10 Feb 2016 16:14:26, Wed, 10 Feb 2016 20:20:17, Wed, 10 Feb 2016 20:24:33
, Thu, 11 Feb 2016 15:53:50, Tue, 9 Feb 2016 18:31:21
, Tue, 9 Feb 2016 18:29:25
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